Table 4. Multivariable analysis comparing age at SLE onset and the clinical and serological manifestations with univariable analysis p values <0.20.

<18 versus ≥18	χ2	OR	95% CI		p Value	18–49 versus ≥50	χ2	OR	95% CI		p Value
			LL	UL					LL	UL
Proteinuria	23.90	3.03	1.94	4.72	<0.0001	Proteinuria	22.24	2.98	1.89	4.68	<0.0001
Malar rash	12.65	2.13	1.40	3.23	0.0004	Cellular casts	10.38	4.00	1.72	9.30	0.0013
Anti-dsDNA	12.17	2.08	1.38	3.14	0.0005	Photosensitivity	6.70	0.63	0.45	0.89	0.0097
Haemolytic anaemia	9.18	2.50	1.38	4.52	0.0024	Anti-nRNP	6.44	1.82	1.15	2.89	0.0112
Arthritis	6.40	1.89	1.15	3.09	0.0114	Anti-Sm	6.11	2.77	1.24	6.20	0.0134
Leucopenia	4.04	1.53	1.01	2.31	0.0445	Anti-dsDNA	5.37	1.62	1.08	2.45	0.0205
Anti-nRNP	2.67	0.61	0.34	1.10	0.1020	Seizures	4.98	2.88	1.14	7.29	0.0256
Pericarditis	1.44	1.34	0.83	2.17	0.2301	Oral ulcer	3.47	1.46	0.98	2.18	0.0624
Thrombocytopenia	0.86	1.26	0.77	2.07	0.3550	Thrombocytopenia	3.42	1.67	0.97	2.87	0.0645
aCL IgG	0.44	1.15	0.76	1.75	0.5094	Malar rash	2.01	1.30	0.91	1.86	0.1564
						Pericarditis	1.97	1.43	0.87	2.34	0.1608
Cellular casts						Arthritis	1.49	1.25	0.88	1.78	0.2224
Men	1.05	0.40	0.07	2.31	0.3057	Pleuritis	1.15	1.24	0.84	1.84	0.2841
Women	9.01	2.18	1.31	3.64	0.0027	Leucopenia	0.51	1.15	0.79	1.67	0.4751

Adjusted for gender, race and disease duration. p Values are reported without correction for multiple testing.

With a Bonferroni correction a p value of <0.004 is considered significant. p Values <0.05 were considered highly suggestive.

aCL, anticardiolipin antibodies; LL, lower limit; SLE, systemic lupus erythematosus; UL, upper limit.